What’s an Air Pocket, anyway? (also, holes in the space/time continuum)

My friend came back from vacation the other day and one of the first things she told me was that they had a tough few moments on the flight on the way back – that they hit an air pocket and experienced a few drops. Which got me thinking. What exactly is an air pocket, and how is it different from turbulence?

Most times for me, I like to imagine that an air pocket is actually a weak point or a hole in the fabric of space and time and the plane’s abrupt drop is because of a change in frequency. I mean, if we learned anything from Fringe (can they please bring back that freaking show?) and later on from the Flash, alternate earths have different frequencies. It logically follows that if the plane flies through a weak spot, electrical controls will briefly go haywire, thus causing brief turbulence. Can I get a job at Massive Dynamic now? #science

Sometimes, the phrase “air pocket” conjures images of a plane flying into a huge bubble…(kind of like that scene in Oz the Great and Powerful when James Franco is in the bubble and they squeeze through the other bubble to get to munchkin land).

Anyway. Apart from my two totally valid explanations, there exists a simpler and correct one. Live Science eliminates any difference between turbulence and an air pocket and says that it is basically the same thing. They explain that it occurs when both updrafts and downdrafts hit the plane at the same time from different directions.

The Collins dictionary defines it as “a localized region of low air density or a descending air current, causing an aircraft to suffer an abrupt decrease in height.” Sounds technical and scary.

There are actually different types of turbulence. Generally, pilots can detect this based on cloud formations, pre-flight weather reports, cockpit radar or updates from other pilots, but the most dangerous type – called “clear-air” turbulence – is a little more difficult to predict as this occurs in perfectly clear, innocuous looking sky. The US FAA defines it as “air movement created by atmospheric pressure, jet streams, air around mountains, cold or warm weather fronts or thunderstorms. It can be unexpected and can happen when the sky appears to be clear.” That leaves the pilots, attendants and passengers unprepared to buckle their seatbelts or finish their coffee.

So whatever you call it, air travel remains relatively safe. In stats released in 2017 by the FAA, only 44 people were injured due to turbulence in 2016. Stats from previous years rarely jump above 50 people, which is pretty low considering the amount of flights that take off every day from every city in the US, and quite a few of those injured are flight crew who would not have been buckled in.

So there you have it. Three potential explanations. You can go with the third one if you want, but to the keen Observer (see what I did there?), I choose the Fringe one.